In the prior art, idle reduction has been known to stop an engine during a stop of a vehicle, such as an automobile, and restart the engine at the time of starting the vehicle, in order to reduce fuel consumption and gas emission during the stop of the vehicle. It is preferable to perform idle reduction when the automobile stops for a relatively long time, for example, when the automobile stops at a traffic light. Idle reduction in the case of a short stop time, for example, during a traffic jam causes a problem that a stop and a restart of the engine are repeated frequently. In order to solve this problem, a variety of techniques have been known to predict, when an automobile stops, whether the stop time is long or short, based on, for example, application of brake, the accelerator opening and the gearshift lever position of the automobile.
For example, Patent Literature 1 discloses an engine control device that stops an engine upon satisfaction of a specified engine stop condition, such as braking operation, wherein a stop of the engine is prohibited when the vehicle speed is less than a predetermined value and no brake pumping operation is detected. Patent Literature 2 discloses a technique that identifies the type of the driver's vehicle stopping operation, such as application of foot brake, application of parking brake or gear shifting, and determines an expected stop time, which is specified in advance corresponding to the type of the vehicle stopping operation.